Elastic moduli and hardness of c-Zr2.86(N0.88O0.12)4 having Th3P4-type structure

The equation of state of the recently discovered oxygen-bearing cubic zirconium (IV) nitride, c-Zr2.86(N0.88O0.12)4, was measured at room temperature in a diamond anvil cell using x-ray powder diffraction combined with synchrotron radiation. From these studies the bulk modulus B0 = 219(13) GPa and its first pressure derivative B0′ = 4.4(1.0) [or B0 = 223(5) GPa, for B0′ fixed at 4] were obtained. Applying nanoindentation techniques the reduced modulus Er ≈ 220 GPa and hardness H ≈ 18 GPa were measured for porous c-Zr2.86(N0.88O0.12)4. The shear modulus of c-Zr2.86(N0.88O0.12)4 was estimated to be at least G0 = 96(13) GPa using the experimental data of B0 and Er, exclusively